There is an uneven administrative-territorial division in Ukraine. There are 490 rayons in the country, which vary greatly both in population and in area. For example, in the Tyachiv (Zakarpattia Oblast) and Kharkiv Rayons there are more than 170 thousand residents, while the Velyka Bilozerka (Zaporizhzhia Oblast), Kolomak (Kharkiv Oblast) and Poliske (Kyiv Oblast) Rayons have population of less than 10 thousand people; the area of the ​​Ovruch Rayon in the Zhytomyr Oblast (more than 3,000 sq. km) exceeds tenfold the area of ​​the Hertsa Rayon in the Chernivtsi Oblast (just over 300 sq. km).
At the same time, the powers of the rayon level authorities are in each case identical.
Therefore, reforming the rayon (sub-regional) level is a reasonable and logical continuation of the process of forming amalgamated hromadas.
Ukraine has obligations in the field of European integration and adaptation of European Union law. Therefore, in deciding the future fate of rayons’ organisation, the requirements of Regulation (EC) No 1059/2003 of the European Parliament and of the Council of 26 May 2003 on the establishment of a common classification of territorial units for statistics (NUTS) should be taken into account. In particular, this document recommends the population of the NUTS-3 territorial unit (corresponding to the sub-regional (regional) administrative unit in Ukraine) to be from 150 to 800 thousand people.